Precooler for shipping compartments



B. WILSON PRECOOLER FOR SHIPPING COMPARTMENTS Sept. 26 1950 Filed April 17, 1946 8 Sheets-Sheet 1 INVENTOR .BRo ADUS Wmsou g Wow Sept. 26, 1950 w so PRECOOLER FOR SHIPPING COMPARTMENTS 8 Sheets-Sheet 2 Filed April 1'7, 1946 E-ECEE:

Iuvzuroa BROADUS Wmsou 1%flu/ ATTORNEY p 1950 B. WILSON 2,523,749

PRECOOLER FOR SHIPPING COMPARTMENTS Filed April 17, 1946 8 Sheets-Sheet 5 INv ENTOR ,BRoAous wlLsow ATTORNEY Sept. 26, 1950 B. WILSON PRECOOLER FOR SHIPPING COMPARTMENTS 8 Sheets-Sheet 4 Filed April 17, 1946 INvENToR BRoADus Wu ..soN

ATTORNEY Sept. 26, 1950 Filed April 17. 1946 B. WILSON PRECOOLER FOR SHIPPING COMPARIMENTS 8 Sheets-Sheet 6 INVENTOR BY- (EW 77% JM ATTORNEY P 6, 1950 B. WILSON 2,523,749

PRECOOLER FOR SHIPPING COMPARTMENTS Filed April 17, 1946 8 Sheets-Sheet '7 Broad/us 14/113012 M 7M2 .AM

' IL .v i 1 24 f28 %73 5 M Sept. 26, 1950 B. WILSON PRECOOLER FOR SHIPPING COMPAR'I'MENTS 8 Sheets-Sheet 8 Filed April 17, 1946 64 M211 ZWQUAM ATToaN 5v Patented Sept. 26, 1950 PRECOOLER FOR SHIPPING COMPARTMENTS Broadus Wilson, Raleigh, N. 0., assignor to Aeroglide Corporation, a corporation of North Carolina Application April 17, 1946, Serial No. 662,808

(Cl. s2' 24) Claims.

This invention relates to apparatus for precooling quantities of fruits or vegetables prior to shipment. In shipping perishable products such as crated fruit it is customary to pre-cool the products after they have been packed in a refrigerator car but before shipment has begun. Not only does such pre-cooling prevent much spoilage that would otherwise occur, it also reduces to a minimum the expenses of icing the car during transit.

I-Ieretofore it has been customary to pre-cool a loaded refrigerator car by circulating chilled air through the lading from supply and exhaust conduits temporarily inserted into the car, the air being cooled by passing over coils located externally of the car. Portable air cooling and cir culating mechanisms temporarily set up within the car itself have also been proposed. However, neither method has proven entirely satisfactory. In the first case, the apparatus, particularly the air conduits, are bulky and dlfi'lCllll] to handle expeditiously. Also it is difficult to seal the space between the conduits and the door opening as is necessary if large power losses are to be avoided and rapid cooling attained. In the second case, the apparatus heretofore used, while temporarily located in the car itself and efficient and satisfactory in most respects, has been so large as to tend to limit the maximum loading of the car that would otherwise be possible.

It is therefore an object of my invention to provide a pre-cooling unit that may be quickly and easily inserted into and removed from a loaded car of fruits, vegetables, or other perishable products', and that requires a minimum of space above the load for placement.

A further object is to provide a pre-cooling unit in two sections wherein one section may first be inserted in the space between the top of the lading and the top of the door opening, then raised to the top of the car, to thereby afford a space within which a second unit or section may be inserted.

Another object is to provide a pre-cooling apparatus constructed in sections, as aforesaid, in which a first section comprises an air-circulating unit and a second section comprises a unit for circulating chilled liquid in heat-exchanging relation with air circulated by the first section.

A still further object is to provide a truck unit for handling the aforesaid sections expeditiously and for facilitating their placement in, and removal from, a loaded car or other shipping compartment.

Another object is to provide a blower section formed of two parts relatively movable in 2. normally-vertical direction, together with powerdriven elevating means whereby one part may be elevated with respect to the other when the Still another object is to provide a novel track and supporting unit for supporting the sections of the cooling unit within the car.

Another object is to provide a truck adapted to support the two sections aforesaid, and to individually mount them for guided translation showing the parts in position just prior to movement of the blower unit into a car.

Fig. 2 is an elevation of the right side of the apparatus in position ready for movement of the blower unit into a car loaded with crates of fruit or vegetables.

Fig. 3 is a front elevation showing the blower unit elevated into the top of a car and the cooling or coil unit moved into position over the lading in the space previously occupied by the blower or fan unit.

Fig. 4 is a perspective detail view showing one of the four elevator screws for the track frame supporting the blower unit, whereby the heighth of the tracks may be adjusted for different types of cars and heighths of lading. Fig. 5 is a perspective View of the forward half of the blower track support, it being understood that the two ends are essentially of the same construction, the cooling coil elevating motor and its driving connections being omitted for clarity of illustration.

Fig. 6 is a detail view taken on a plane indicated by the line 6-6, Fig. 5.

Fig. '7 is a perspective view on an enlarged scale, of the front portion of the fan unit.

Fig. 8 is a front elevation of the frame of that part of the fan unit mounting the fans and their driving motors.

Fig. 9 is a detail elevation on the same scale as Fig. 8, showing one of the two identical motor supports.

tical cooling coil support tracks, and its elevating screws, together with the coil unit translatably mounted thereon.

Fig. 11 is a sectional detail view taken upon the line[ l -H of Fig. 10.

Fig. 12 is a plan view of the blower track support showing the arrangement of the motor, jack shaft, worm shafts, and connections for elevating the cooling coil unit with respect thereto.

Fig. 13 is an end elevation of the support for the ends of the tracks within the car remote from the pre-cooling apparatus. 7

Fig. 14 is a detail view showing upon an enlarged scale the track-supporting lugs as seen upon the line i k-I4, Fig. 12.

Fig. 15 is a plan view of the end of one of the two tracks within the car remote from the apparatus.

Fig. 16 is a plan view of the track guide for spanning the space between the loading platform and car.

Fig. 17 is a section. taken upon the line I'II'I, Fig. 16, showing the supporting jacks and the screws for securing the track guide in position.

Fig. 18 is a vertical cross-sectional view taken in a plane identified by the line I8I8, Figure 2,

Figure 19 is a horizontal cross-sectional view taken in a plane identified at I9--I9, Figure 2,

Figure 20 is a horizontal section taken in a plane indicated by the line 2U20 of Figure 2,

Fig. 21 is an end view of a form of the invention, using a pulley and cable arrangement for elevating the blowers within the car, and being adapted for handling by a crane.

Fig. 22 is an enlarged view of a portion of Fig. 18, showing one of the cable and guide pulley units and its mounting.

Referring in detail to the drawings, the numeral 5 indicates generally a carrier base or frame. As best shown at Fig. 2 this frame is formed of angle irons, preferably welded together, and consists of four uprights identified by numerals I to 4, inclusive, at the corners of a rectangle having a width a little less than the door opening of the car which the apparatus is intended to service, and a length equal to about 75 per cent of the length of the blower and coil units hereinafter described. The uprights I and 3 are rigidly connected by side horizontals 6 and I, Figures 2, 4, l8 and 19. Likewise uprights 2 and i are connected by side horizontals 6 and I,

Figures 1, 18 and 19. Front uprights I and 2 are connected by horizontals 8 and 9, Figure 3 and rear uprights 3 and 4 are connected by horizontals 8 and 9, Figure 18. It will be noted that the upper horizontals 6,6, 8, 8' are attached to the verticals about half way between the ends thereof. The carrier base 5 is mounted upon swivel casters If) so that it may be rolled about on the loading platform P, Figures 1 and 2.

As seen at Figures 3, 4 and 19, a plate II extends across the frame 5 at the forward lower end thereof and is fixed to the coplanar horizontal flanges of lower horizontal side members I and I and forward end member 9. This plate forms a support for a motor I2. Fig. 4 shows the forward right corner of the carrier base or frame and its associated portion of the blower track support and it will be understood that, except for the belt driving pulley I6 there shown, the other corners are of similar constrduction. A substantially square plate I3 is fixed to the upper flanges of members 5 and 8 and carries a bearing I4 j ournalling a shaft I5 to which are secured a belt pulley I6 forwardly of horizontal 8, a worm I7, and a chain sprocket I8. The pulley is connected by belt I8 with a pulley on the shaft of motor I2 as clearly shown upon Figure 3. A worm or Boston gear 20 is mounted in an antifriction bearing, not shown, for rotation upon plate I3, and meshes with worm I1. Gear 20 is threaded to receive an elevating screw 2| that has an eye formed at its upper end, secured by bolt 22 to one side member 23 of a blower track support, subsequently described.

Sprocket I8 carries a chain 24 which passes over and about an identical sprocket I8 on a shaft 28 mounted similarly to shaft I5, at the other side of the frame, whereby the two shafts are synchronously rotated. As seen at Figures 2 and 19, shaft I5 extends along the side of the frame to the rear thereof, where it is journaled in a bearing and has fixed thereto, a worm I'Ia identical with I! and in mesh with a worm gear 24 threadedly engaging an elevating screw 25, identical with 2|. It will thus be seen that the blower track support member, of which angles 23, 26 and 21, Fig. 4, are parts and which will be subsequently described in detail, is carried by four identical elevating screws, one at each corner, that screws 2! and 25 at one side are elevated by rotations of worm gears 20 and 24, respectively, which, in turn, are rotated by shaft I5. The counterpart of shaft I5, is identified at 28, Figures 3, 18 and 19, where it is seen to be journaled in a forward bearing 29 and a second like bearing 29 at the rear. Shaft 28 carries a sprocket I8 and worms 51b and Ilc, Figure 19, identical with those on shaft I5, each worm being in mesh with worm gears 20a and 24a corresponding to gears 20 and 24. Since shafts I5 and 28 are connected by chain 24' for synchronous rotation, operation of motor I2 acts to synchronously rotate all four worm gears and thus to elevate the blower track support of which the forward half is shown at Figure 5 and the rearward half at Figure 20. Control of motor I2 is effected by a switch 30 conveniently mounted upon a control panel 3| fixed in vertical position to the frame 5. A junction box for lead-in wiring to motor I2 is mounted on panel 3|, as indicated at 32, Fig. 2. Motor I2 may be a conventional, reversible, single-phase machine of one-third or one-fourth horsepower.

The blower track support which is mounted at its four corners upon the upper ends of screws 2 I, 4,5, 25, and 25, is built up from standard metal bars and preferably has welded joints. As shown at Fig. 5, it is in the general form of a parallelopiped. The two forward uprights 26 and 33 are joined at their lower ends b the end piece 21 while the two rear uprights 26' and 33 are similarl connected by end piece M8. Upright 33 has a bar 34 secured in slightly overlapping relation to its rear outside edge. A like bar 34' is located at the rear corner of the support and the ends of 34, 34' and center bar 35 are joined by an angle 36 at the bottom, and a bar 37 at the top. See Figures 5, 6 and 20. A pair of side plates. 38 and 39 having about two and one-half times the width of bar 31, are secured to its opposite sides and t uprights 3 3, 35 and 34, as by bolts or rivets. The relation is such that the upper edges of side plates 38 and 39 project about three-eights of an inch above the top of bar 31, to form therewith a channel or track within and along which rollers 46, 41 and 48,, of the fan housing, are adapted to roll. See Fig. 1. The other side is similarly constructed so that it is sufficient to identify front upright 26, rear upright 26', lower angle 23, vertical bars 40, Al and track bar 42 and side plates 43 and 44. Also identified are jack screws 2I and 45 at the opposite front corners of the support and 25 and 5' at the corresponding rear corners. Figure 20 shows the rear portion of the frame and its mounting between uprights 3 and 4 of frame 5 Referring to Figures 12 and 20, triangular plates I 13 to I46 are secured at the corners of the frame and brace the same against distortion in a horizontal plane.

By the foregoing construction, rotation of motor I2 synchronously rotates the four worm gears 2051., 24 and 24d at the fourcorners of the blower track support, so that the tracks are elevated equally to such heighth as may be necessary to bring the tracks a little above the top of the lading in the car.

The blower or fan unit consists of two parts that are relativel movable in a Vertical direc tion by means of a self-contained power-driven elevator. Figures 7 and 18 show the front end portion of the fan unit. A pair of built up side plates or beams 49 and are provided. Each beam comprises in generalga rectangular steel plate reinforced along its edges with lengths of angle iron, and also having transverse reinforcements, as shown in Figs. 1,- 2 and 7. Connections between the several'component parts of each beam may be effected by welding or riveting, as desired. As best seenin Fig. 2, the two beams 49 and 50 are connected at their front upper corners by a beam 5| which may consist of a length of angle iron. The beams are connected at the rear upper corners by a second beam not shown but identical with El. Beam 49 has a bearing pad 52 secured to its upper edge and spaced a little back of its forward edge. This pad has a bearing 54 journallng a shaft 55. A worm 59 is fixed to shaft 55 and meshes with the threaded worm gear 5? journaled on pad 52 by an antifriction thust bearing, not shown. A small sprocket wheel 58 is secured to shaft '55 adjacent bearing 54.

Shaft 55 extends forwardly through a bearing 59 and has a belt pulley 89 secured to its forward end. A motor BI, which may be a reversible, single-phase machine of fractional horse power, is bolted to beam 5! and has a belt pulley 62 on its shaft. Belt 63 connects pulleys and 62. These parts are duplicated at the other side, except of course, for pulle 60, so that it is deemed sufiicient merelyto identify shaft 64 (Figs. '7 and 18) bearing pad 65, worm gear 86, and sprocket 87. A bracket 68 is attached tobeam M and carries an idler sprocket 69 journaled on a stud I0 that may be adjusted along a slot II in bracket 68 to thereby effect proper tension in a chain I2 connecting the identical sprockets 58 and 81 by. synchronous rotation, as will be obvious from inspection of Fig. 7. From Figs. 1 and 18 it will be noted that shafts 55 and 64 extend t the rear end of their respective beams and that each carries three worms, in mesh with worm gears such as 51, I3 and I4 for shaft 55, and see Figs. 2 and 18), 69, 76 and IT for shaft 84, whereby rotation of motor 6| drives all worms synchronously. As seen at Figure '7, a pair of horizontal track members I20 and I2I which may comprise length of channel iron with one side turned outwardly to form a reverse flange, are secured to the inside faces of the respective beams 49 and 50. These members form a track on and along which the cooling coil unit may be moved into the car when the blowers have been elevated in the manner subsequently described. Each of the worm gears 51, I3, 54, 69, I6 and 11 engages a threaded rod as shown at I8, Fig. 7, for worm 51 and at Fig. 18 for worm gears I4 and TI and their threaded rods 80 and 83, respectively. These rods or elevator shafts are identified-as I8, I9 and 80, for the left-hand side of the machine, as seen in Fig. 1, and 8|, 82 and 83, for the right-hand side as seen in Fig. 2. Rods 'IB and 8| form a pair, as dorods I9, 82 and 80, 83. Each pair of rods are attached at their top ends by cross pieces of angle iron 84, 85 and 86, Figure 1, which may conveniently be welded or bolted to the rods,

8 The cross pieces are connected at their central portions by a heavy channel section 81, and at their ends by angle sections 88 and 89 extending horizontally along each side. See also Fig. 18.

Fig. 8 shows the front end of the frame mounting the blowers and their driving motors. It will be understood that this construction is typical and that a substantially identical construction is provided at rods I9 and B2 and at B0 and B3. The cross piece 84, also identified in Figures 1 and '7, has vertical angle sections 90 and 9I attached thereto a distance from its end sufficient to clear plates or beams 49 and 50. At their bottom ends, these verticals are united by a plate 92, reinforced along its top and bottom edges, by cross pieces 93 and 94. At the left lower edge, a longitudinal channel or stringer 95 also shown in cross section upon Fig. 18, is connected with cross pieces 93 and 94.

the rear to vertical 90a, Fig. 18. channel or stringer 96 (Figs. 8 and 18) extendsv along the lower right corner of the fan frame and is attached to front vertical SI and rear vertical 9 la, Fig. 18.

In the model selected for illustration, two standard centrifugal blowers are used, each connected to be driven by-a respective three-phase motor of about three horse power. In Figs. 1 and 2, the forward blower is identified as 91 and its driving motor as 99. The rear blower is shown at 98 and its driving motor at I00. Motor 99 also appears in Figs. 7 and 8 and motor I00 in Fig. 18. Each blower is journaled in a top bearing carried by central channel 81, and a lower bearing carried by a cross channel such as that shown at IOI, Fig. 9, for blower 98, the center line of whose shaft is shown at I02. From Figs. 9

' and 18 it will be noted that the mounting for motor I00 comprises a pair of vertical angle sections I03 and I04. The sections are secured at their lower ends to channel 96 and section I03 is attached at its upper end to cross piece 89. The two vertical sections are connected by four straps I05, I06, I01 and I08 to form a rigid support to which the base of motor I00 may be bolted with its shaft vertical. The frame for motor 99 is of identical construction. As seen in Fig. 8, motor 99 has a pulley I09 upon the lower end of its shaft, connected by a belt II! to the pulley III] of blower 91. As clearly shown in Fig. 1, shroud plates H2 and H3 are positioned about the rotor of blower 91 to direct air laterally in oppositely-directed streams. Likewise, shroud plates I I4 and I I5 are provided for blower 98. Three-phase current is supplied to motors 99 and I00 by wiring, not shown, leading from receptacles I I6 and II! (Figure 8) mounted upon the forward bulkhead plate H8. By the foregoing construction, operationof motor 8| synchronously rotates all six worm gears 51, 66, I3, I4, 19 and TI, to elevate the blower frame, the blowers and their motors, to a maximum elevation a little above the top edges of beams 49 and 50, wherein'the fan outlets are unobstructed by said beams and the blowers when in operation, draw air upwardly over the cooling coils of the cooling unit when the latter is rolled into the car on tracks I20 and I2 I, into position beneath the blower frame, and impel the chilled air horizontally toward both ends of the car. The bottom of the blower frame is substantiallyopen and unobstructed.

The cooling coil unit includes a generally rectangular frame with open top and bottom and This stringer extends. the full length of the frame and is attached at. Likewise, a.

7. upon which a number of connected coils or pipes are carried. The frame has a series of aligned rollers on each side, adapted to mount the unit for translation into the car as will presently to be described.

The support for the coil unit consists of two identical track members. One of these members is shown at I4I, Figs. and 11, and comprises a central strip of metal I22, to opposite sides of which are riveted a pair of wider plates I23 and I2 5. The plates are arranged with top edges a little above the top edges of central strip I22 to form a channel or track in and along which the rollers on the sides of the coil frame may travel. As shown in Fig. 11, the plates I23 and I24 project beyond strip I22 at each end of the track, to receive therebetween vertical bars such as I25. The vertical end edges of the plates project a little beyond the outer vertical side edges of bars I25 and vertical side plates I26 and, I2! are rigidly attached to I25 with their outer vertical edges fiush with the aforesaid end edges of plates I23 and I24 to thereby form a vertical channel or guideway I3 I. The other end of the track member is of like construction so that it is sufiicient to identify vertical bar or strap I28, Fig. 10, and vertical side plates I23 and I38. A central vertical brace I32 has its upper end fixed between plates I23 and I24, and a reinforcing rod I33 is attached at its ends to strip I22 between plates E23 and I24 and passes beneath and is there secured to the lower end of brace I32. A jack screw I38 is fixed at its upper flattened end to and between the front ends of plates I23, and I2 5. A second jack screw I35 is similarly fixed to and between the rear ends of plates I23 and IE3. As previously stated, the other of the two track members is identical in construction with the one just described.

Each of the track members just described is of a length to have a smooth fit between a respective pair of front and rear uprights of the blower track support. For example, at the right hand side, the front upright, previously described, is identified at 23 and appears in Figures 3., 4, 5, 11, and 12. The right rear upright, is identified at '26, Figure 12. The right track member of the cooling coil support, shown in Figure 10, is guided for vertical movement between and along uprights 26 and 23' by reason of the guideways such as I 3I, Figure 11, and coacting projection I36, secured to upright 23. The construction whereby the rear upright 25 guides the righttrack member, is identical in all respects with that shown at Figure 11. The left track member of the cooling coil support is, of course, identical with the right member, just described, and is guided for vertical movement by and along left front upright 33, Figures 3, 5, and 12, and left rear upright 33', Figure 12, of the blower track support. Each of these uprights has a projection I36 welded or otherwise secured in vertical position along its face. These projections have a Width a little less than that 0f guideways I3'i. By this construction each track member Isl and MI, Fig. 18, is mounted for guided vertical movement on and along the blower track support and while moved as a unit therewith on operation of motor I2, is also independently movable in vertical direction relatively to the blower track support by mechanism presently described;

Two p irs of Boston gears or worm gear nuts, I31, I38 and I39, 48, support the tracks I4! and I 32 by engag ment with the respective jack screws, of which, I34 and I35, for the right hand track I4I, have been described. The gears I31 and I38 of one pair, (see Figure 12) are rotatably mounted by antifriction bearings, not shown, on the front and rear, triangular brace plates I43 and I44, respectively, of the blower track support. A shaft I il is journaled in bearings carried upon the end horizontal members 21 and I48 of the blower track support and has worms I49 and I50 fixed thereto in mesh with the adjacent Boston gears, I37 and I38, respectively. In addition, shaft I47 has affixed thereto a sprocket I55.

The second pair of Boston gears I39 and I40 are journaled on horizontal plates I45 and I48 of the blower track support. A second shaft I5I is journaled in bearings fixed to the other ends of the front and rea horizontal members 21 and I48. This shaft has worms I52 and I53 affixed thereto at opposite ends, each in mesh with a respective one of the second pair of Boston gears I33 and I48. A small sprocket I54 is fixed to the forward end of shaft I5I. This sprocket is equal in size with and is positioned laterally opposite sprocket I55 and is connected for synchronous rotation therewith by a chain I56. The two shafts I41 and I5I are driven by a fractional horsepower motor i5! bolted to the under side of a plate I58 that, in turn is attached at one end to the horizontal flange of horizontal member 21, and at the other end to a second horizontal membe I59, spaced rearwardly of member 21 and affixed at its ends to the side members 23 and 36. A counter-shaft 68 is journaled in bearings carried by horizontals '21 and I 59. This counter-shaft has a small sprocket IBI fixed thereto which is connected to drive sprocket I82 fixed on shaft I5I by a chain I63. Counter-shaft I68 also has a large belt pulley I84 fixed thereon, connected by belt I to be driven from a small pulley I66 upon the shaft of motor I51. Thus, as motor I51 operates, it drives counter-shaft I50 and shafts I41 and I5I, at reduced speed, to rotate all four Boston gears I37 to M8, inclusive, in synchronism, and thus acts through jack screws I34, I35, I34 and I35, Figs. 1, 2, 10 and 20, to elevate in unison the two coil unit supporting tracks and the cooling coil unit 206 thereon. Plate I58, motor I51 and its driving connections with shaft I5I are clearly shown upon Figure 12 and have been omitted from Figure 5 to more clearly illustrate the frame construction.

The cooling coil unit itself, identified generally at 206, Figs. 1, 2, 3 and 18, is of conventional construction so that it is deemed unnecessary to show and describe it in detail. Suffice it to say that it consists of a generally rectangular framework with open top and bottom, and enclosed by metal plates on its four sides. A supply header (not shown) and an exhaust header extend in horizontal, vertically-spaced relation across the front of the unit. These headers are connected by coolant-conducting heat-exchange piping which, if desired, may have fins thereon to increase the heat-exchange area. Supply and exhaust couplings i6! and I68, Figures 2 and 3, are in communication with the respective headers and afford means by which chilled liquid such as brine, from an adjacent refrigeration unit (not shown) may be conducted to and forced through the coils. If desired, bafiles may be inserted between coils or groups of coils to increase, in a known manner, the length of the flow path of the air over and about the coils.

Any suitable known heat-exchange means may be satisfactorily employed, and reference is made to the co-pending application of Hipolit M. Hincz, Ser. No. 589,917, filed April 23, 1945, now Patent 2,477,250, dated July 26, 1949, for a specific disclosure of one suitable form of cooling coil unit, as just described.

Current may be led to the several motors from switches located upon panel M, by lengths of flexible insulated cable (not shown). The control of all motors at a central panel, enables control by one person, and facilitates accurate and precise operation as well as rapid insertion of the unit into a car and withdrawal therefrom. Automatic" stoppage of the motors is contemplated by vertically adjustable stop switches located in the paths of the several tracks, or parts moving therewith, whereby each of the three elevator motors is automatically stopped when the pair of tracks under its direct control, reach their desired elevation. As seen in Figs. and 18, the sides of the cooling coil unit 288 carry rollers 286a by which the unit is mounted for easy translation on and along tracks MI outside the car, and tracks I and I2I which, as previously described, are secured horizontally to the inside surfaces of beams 49 and 58 of the blower or fan unit. See Figure 7 inside the car.

The means for supporting the apparatus within the car is disclosed at Figs. 13, 14 and 15, and consists of a pair of angle irons I18 and Ill having a length approximately equal to the width of the car. A lug is formed at one end of each of the angle irons and is adapted to drop into a hole provided in the adjacent ends of the blower supporting tracks 31 and 4'2 when the latter have been elevated to the prope height by operation of motor I2.

The construction is such that when the lugs are in position, the angles I18 and HI form continuations of the tracks provided by the blower supporting tracks and thus have their horizontal flanges at the same level as the top edges of bars 31 and 42 (see Figure 6). The other ends of angles I10 and HI are supported by a simple framework comprising upright tubes I12 and I13, interconnected at top and bottom by crosspieces I14 and I15. Brace bars I16 and I11 are provided and all parts may be welded together as shown at Fig. 13, to form a unitary frame. A pai of screws I18 and I19 slidably fit the bores of tubes I12 and I13. These screws have their tops connected by a crosspiece I89. Nuts NH and I82 are threaded upon the respective screws I18 and I19 and each bears upon the top of its tube. Duplicate lugs I83 and I84 are welded in upright position to the ends of crosspiece I88, to project a short distance above the top edge thereof. Each lug is notched at its top edge as indicated at I85, Fig. 14, the notches being dimensioned to receive the shank of a bolt I86 such as is shown for track I10 in Fig. 15. Each bolt may be welded to its track and have a length a little greater than the thickness of lugs I83 and I84. Thus when the frame, indicated generally by the numeral I81, is in position in the car, nuts I8! and I82 are adjusted so that, when tracks I10 and HI are in position, they are slightly above the lading' at that end. When bolts I88 are seated in the notches I85 of lugs I83 and I88, the tracks are firmly held against lateral and longitudinal movement. At the other end, tracks I18 and HI are supported by the blower tracks, as previously described, and may be adjusted to the correct elevation by operation of reversible motor I2.

I have also provided a useful auxiliary in the 10 form of a guide track frame for the pre-cooler, which guides and supports the same into position within the car door opening. Such frame is indi-; cated generally by the numeral I88, Fig. 16, and comprises a pair of flat track members I89 and I98, relatively narrow at the ends within the car and flared at the ends supported upon the loading platform. Track member I89 is reinforced along its edges by lengths of angle iron I9I and I92 bolted o riveted thereto, as shown in Figs. 16 and 17. Likewise, track member I is re-. inforced by angles I93 and I94. These side angles act as guides to positively direct the pre-cooling unit into proper position within the car door opening. The two tracks thus formed are connected at one end by angle I95, and at the other end by angle I 95. Theseare welded to the tracks to rigidly hold the same in generally parallel relation. From Fig. 17 it will be noted that a nut such as I91, is welded to the lower side of the car end of each track and is threaded to receive the screw I98 of a jack member having a base 209 relatively to which the screw may be turned by a lever inserted into holes I99 of a collar 20L This, collar is fixed to the screw and is journaled in base 288, to thereby accurately adjust the elevation of the ends of the tracks within the car, as desired.

Nut members 202 and 203 are welded to the ends of the vertical flange of connector I06 and are threaded to receive screws 284 and 285. By turning these screws, their ends may be forced against the vertical side of the loading platform to thereby prevent any possibility of thetrack shifting away from its proper position in the car.

Operation In using my invention, the tracks I18, I11, are first positioned over and across the lading at the car doors. The frame I81 is positioned between the load and the doors opposite those through which the machine is to be inserted into the car, and nuts IBI and I82 are adjustedso that with the tracks resting on cross piece I88, as shown in Fig. 13, the ends of the tracks are slightly spaced above the top of the lading. The other ends of the tracks may at this time, rest upon the lading. The guide track frame I98 is placed in position and its ends within the car are vertically adjusted,'by means of the supporting jacks, so that the frame is substantially level] The pre-cooler is now moved over and along the tracks of frame I88 until its rear end is closely adjacent or in contact with the car lading. The electrical plug-in connections are made leading to the several motors, and motor I2 is operated until tracks 31 and 42 are at the same level as the desired level of tracks I18 and I1! within the car. The lugs on the rear ends of tracksI'Ii! and HI are now engaged with apertures in the ends of the blower unit tracks so as to be supported thereby at that end.

The tracks inside the car are now supported at both ends slightly above the lading.

The blower unit comprising interconnected beams 49 and 58 and parts carried thereby, as shown in Figures 1, 2, 7 and 18, is next rolled into the car. During this operation, rollers 46, 41 and 48, on beam 49, Figs. 1 and 18, roll along aligned tracks 31 and HI, and rollers 48', 41, and 48, Fig. 2, roll along algned tracks 42 and I10. When the blower unit is in position within the car, motor BI is operated and by the mechanism previously described, elevates the blower fram blowers 91 and 98, and their driving motors 99 and Itiil, into position closely adjacent the top of the car as shown in dotted lines in Fig. 2, so that the car ceiling itself acts substantially to close the top of the blower frame. This elevation of the blower frame, provides a space between beams 49 and 50 into which the cooling coil unit 206 may be moved as will be clear by reference to Figs. 7 and 18. In Fig. 18 the blower frame has been elevated to substantially its maximum height while the cooling coil frame is just a little below the proper elevation to enable its rollers 206a to roll into the ca on tracks E22 and I2I. Motor I57, Fig. 3, is then operated to elevate coil unit 236 until the tracks MI and I42, Fig. 3, are aligned with tracks I20 and HI, carried by the inner sides of beams 49 and 53. The cooling coil unit is then rolled on and along the aligned tracks into position beneath the blower unit. Any necessary vertical adjustments to bring the two units into the desired cooperative relation are made by operation of motor M. The hose connections to the cooling coil unit are made and the valves controlling the circulation of the cooling medium are opened, to circulate chilled brine o other cooling medium through the coils. Plug-in connections to the blower motors are made at H6 and III, Fig. 8, the car doors remote from the pre-cooler are closed and sealed, and the spaces between the pre-cooler and the adjacent door opening are sealed by means of suitable baflies.

The blowe motors are then started and air is drawn upwardly and chilled as it passes over the coils in unit 206. The cold air is then directed outwardly in streams toward both ends of the car whence it passes. downwardly through the lading to rapidly extract heat therefrom. Operation is continued until the entire lading is reduced to the desired temperature. Meanwhile, the car having been iced, when the desired low temperature has been attained, the bafiies are removed, the cooling unit is rolled out of the car and lowered on the frame by reverse operation of motor I51. The blowers are then lowered by reversal of motor 6 I to their initial position between beams 49 and 5%, after which the entire blower unit is rolled out of the car. The tracks I!!! and Ill and frame I8? are removed and the car doors are closed and sealed. The car is now ready for transit.

In Figs. 21 and 22 I have shown a modification for use in connection with a crane mounted, for example, for movement along an overhead track parallel to and offset from the car tracks. In these figures, a built-up frame includes two or more parallel cross bars such as 2H3, adapted to be connected in parallel relation by a pair of stringers 2H and H2. A number of vertical strips 2I3 and 2M are connected at their top ends, with stringers 2|! and 2-I2, respectively, and are united attheir lower ends by Z-bars 2I5 and 2I6. A number of vertical strips such as 2! I and H8 are secured at their upper ends to the inside faces of the res ective Z-bars and depend therefrom, being united at their lower ends by angles 2 I9 and 220 which are held in horizontally spaced relation by angles such as 22I A second pair of angles 222' and 223 have their vertical flanges secured to the inside surfaces of the upper ends of strips 2 l and 2I8' so that their horizontal flanges form tracks supporting the blower unit 224, as hereinafter described.

It will be understood that the strips 2! I, 2I'2, Z-bars 2I5 and 286, and an les 2&9, 225}, 222

and 223, are all the same length, approximately 12 the same length or a little shorter than the blower and coil units. There will be a number of cross bars 2), one at each end of the frame, and a number of others interposed between the end cross bars. Likewise there will be a pair of strips such as 2I3 and 2M at each end and others equally spaced and interposed between the end pair of bars as may be found necessary to give the desired strength and rigidity to the frame. Preferably the number of pairs of strips '24? and 2I3 will be equal to the number of pairs 2I3 and 2M, with each lower strip positioned immediately below the corresponding upper vertical strip. The end cross bars ZII] have means for attachment to sections 224 and 225 of cable, the

other ends of which are connected to respective brackets such as 226 mounted upon a spreader bar 22?. Cables from a crane of any known type are connected to brackets 226 so that the entire pre-cooler may be moved along the aforesaid overhead track with the frame at right angles thereto. The crane may also be operated to raise and lower the frame as desired. The blower unit is generally of the same form and construction as in the species of Figs. 1 to 20 and includes side plates 228 and 229, reinforced by sections of angle iron such as 230 and 23I spaced at intervals along the lengths of the respective plates to form a pair of beams similar to 49 and 50, Fig. 7. These beams are connected at the end portions of their top edges by angles such as 232 to thereby form a frame having an open top, bottom and end. A pair of elongated roller supporting elements 233 and 23 1 are connected as shown to the lower edges of the respective plates 228 and 229. The elements 223 and 224 may be conveniently formed by welding sections of angle to one side of a plate or strip to form a structure generally h-shaped in cross-section. A number of equally spaced ball-bearing rollers 235 and 236 are journaled within the channel of elements 233 and 234 and rest upon the horizontal flanges of angles 222 and 223 whereby the entire blower unit may be translated therealong. The blowers and their driving motors are carried by a frame similar to the one shown in Fig. 7. This frame comprises a pair of end plates such as 23'! reinforced at top and bottom edges by angles 238 and 239 and at their sides by angles such as 240 and 2M. The sides, top and bottom of the frame are of course open except only that the sides may be partially obstructed by the blowers. A pair of shafts 242 and 243 are journaled in brackets such as 244 and 2 55, Fig. 22, at a desired number of points along the top edges of the plates 228 and 223. These shafts extend the full length of the blower frame and project slightly forwardly thereof at the front where they are provided with squared ends adapted to be engaged by a detachable crank. Sprockets 225 and 24'! are fixed upon the forward ends of the shafts. These sprockets are connected for rotation in unison by a chain 248. Each shaft has two or more pulleys fixed thereon as shown at 2 59, Fig. 22. It will be noted that each pulley has a helical groove formed upon its surface and is located between a pair of mounting brackets 2M and 245. In addition each pair of brackets, mounting shaft 242, pivotally mounts a roller such as 258 and so positioned as to maintain a cable 25I adapted to be wound on pulley 249 when shaft 242 is rotated. An equal number of grooved p lleys are fixed to shaft 243 on each of which is adapted to be wound a length of cable as illustrated at 252, Fig. 21. The lower end of each length of cable is fixed to the lower 13 side edge of the frame mounting the blowers and motors. In the models illustrated, a total of six grooved pulleys, such as 249, are used, one being located at each end of each shaft and another pulley being located at the mid-portion of the shaft. Any convenient means not shown, such as a ratchet and pawl device, may be used to hold either or both shafts in position. In the position shown in Fig. 21, the motor and blower frame is shown in lowermost position, resting on the horizontal flanges of track elements 233 and 234. This is the position in which the blower unit is moved into a car to be cooled. It will be understood, of course, that auxiliary tracks such as I'll] and I1 I, Fig. 13, are supported within the car and that when the cooling unit is in proper elevated position before the car door, the'horizontal 'flanges of elements 233 and 234 are in alignment with the aforesaid auxiliary tracks. Thus when the blower unit is within the car, turning of either shaft 242 or 243, will operate to raise the blowers and their driving motors into position adjacent angles 2l9 and 2'20 are in alignment-with the horizontal flanges of track elements 233 and 234. Thereupon the cooling coil unit may be moved into the car in the space between plates 22B and 229 vacated by elevation of the blOWer unit. The cooling coil unit may be substantially the same in construction as the one illustrated in connection with the species shown in Figs. 1 to 20. As seen in Fig. 21, the frame of this unit includes a pair of stringers 253 and 254 Z-shaped in cross section. A plurality of ball bearing rollers, such as 255 and 256, are mounted upon shafts spaced along the aforesaid stringers so that the entire unit may be easily displaced along its supporting tracks into the car in cooperative position beneath the blower unit. Supply and exhaust couplings 25'! and 258 are provided, whereby chilled fluid may be circulated through the coils from a refrigerating plant exterior of the car. This cooling coil unit like the ones shown in Figs. 1 to has closed sides and ends and an open top and bottom so that when theunits are in position within the car air is circulated by being drawn upwardly over and about the coils and I have thus provided a pre -cooling machine thatv maybe placed in position in about ten minutes and removed in half that time. It is rapid, eflicient and simple in operation and, above all, may be entered into the car within a minimum of space between the top of the lading and the top of the car door opening. By providing a sufficient number of pro-coolers, an entire train of cars may be serviced at the same time from a single refrigerator plant thus effecting a great saving of time in getting the crated fruit on its way to market.

By my invention, the rapid cooling of the fruit or vegetables inhibits the start of decay and reduces spoilage to a minimum. spoilage is additionally lowered because of the saving in time between crating and the placing of the fruit upon the market. Furthermore, labor costs are reduced because the power-operated features enable the pre-cooler to be quickly placed in position and even more quickly withdrawn from the car. Shipping costs are reduced because of the increased load per car because of the fact that the 14 blower unit is first inserted into the car, elevated into proximity to the car ceiling, after which the cooling coil unit is moved into the car to occupy the space vacated by the aforesaid elevation of the blower unit.

Many variations are possible where a battery of pre-cooling units are employed. In one arrangement, the platform P is located between two tracks and cooling liquid and current are supplied from overhead conduits extending centrally along and above the platform. Loaded cars on each track may be simultaneously pre-cooled or, as soon as a car on one track is pre-cooled, the unit used to service that car may be transferred to the car opposite upon the other track. It is also contemplated that, instead of mounting the pre-cooling units on casters l0, they may be carried by a crane upon an overhead track extending centrally between two tracks. Supply and exhaust headers for coolant, as well as power lines, may be supported to extend along and parallel with the overhead track, In this man- 'ner, the pro-cooling units may be rolled along the overhead tracks into position instead-of being supported upon the platform P shown upon.Fig. 2. For convenience in such an arrangement, coupling connections may be provided at each end of coil unit 206, each coupling, of course, being provided with a shut-off valve. 1

While I have shown a preferred form of the invention as actually built and successfully operated, numerous changes and substitutions will occur to those skilled in this art. Hence the foregoing disclosure is to be taken in an illustrative rather than a limiting sense; and it is my desire to reserve all such modifications, alterations and substitutions of equivalents as fall within the scope of the sub-joined claims.

Having now fully disclosed the invention, what I claim and desire to secure by Letters Patent is:

In a pre-cooling apparatus for compartments, a frame, a blower unit mounted on said frame, a cooling coil unit mounted on said frame, said units being independent but ada ted to cooperate to cool and circulate gas within a compar'tment, and means carried by said frame to individually support said units for projection therefrom in succession, into a compartment to be cooled, and to position said units therein in juxtaposed, cooperative relationship with said cooling coil unit supported on and by said blower unit.

2. In a pre-cooling apparatus for a shipping compartment having a loading opening, a frame adapted to be positioned adjacent said opening, a blower unit mounted on said frame, a coil unit mounted on said frame and having connections whereby a heat exchange medium may be circulated therethrough from a source external of said compartment, means carried bysaid frame to support said units for separate and individual movement in succession into said compartment, and means to vertically move one of said units Within said compartment to provide therein a space into which the other of said units may be moved juxtaposed. cooperative relationship with said one unit.

3. In an apparatus for pre-coolin shipping compartments, a frame, a first pair of substantially horizontal parallel track members, first means mounting said first pair of members on said frame for elevation with respect thereto, air circulating unit mounted for translation on and along said first pair of members, said aircirculating unit including a support, a blower on was said support, and means mounting said blower 'for elevation with respect thereto, 'a-secondpal of track members, second --means mounting said second pair of track members on said frame beneath and substantially parallel to' said first pair ofv track members and operable to elevate'said second pair of track members with respect to said frame, a cooling coil unitmounted for translation on said second pair of track members, said cooling coil unit'being adapted for translation into cooperative relation beneath said blower when said blower-has been elevated with respect to said support.

'4. A pro-cooling apparatus for a railway refrigerator car, comprising, a first supporting frame adapted to be positioned adjacent the loading opening of said car, a'pair of spaced parallel, normally horizontal track members, elevator means mounting said track members on said frame, and operable to vary the elevation of said track members as a unit with respect to said frame, a second frame adapted to be positioned within said car to form a continuation of said track members within the "car, a blower unit mounted for movement into said car on and along said track members and continuations thereof, said blower unit comprising a truck, a power-driven blower unit, and means carried by said truck and, in'turn, supporting said blower unit, said last nam'ed means being operable to elevate saidblower unit relatively to said truck.

5. A pro-cooling apparatus for a railway refrigerator car comprising, means forming a pair of guide tracks extending transversely across said car through the door opening to the exterior thereof, an air-circulatingunitcomprising first, a truck mounted for guided movement on said tracks into and out of said car, secondly, a blower adapted to circulate air outwardly toward at least one end of said car, and thirdly, jack means mounting said blower on said truck and operable to elevate Said blower with respect to said'truck, a cooling coil unit, and track means mounting said cooling coil unit for movement into and out of said car into cooperative position with and be- A neath said blower when the latter has been elevated by said jack means to a position within said car and adjacent the top thereof.

6. In a pre-cooling apparatus for shipping compartments, a first frame, first and second track means, defining respective superposed first and second substantially horizontal parallel paths, power driven elevator means mounting both said track means on said frame for vertical adjustment with respect thereto, a blower unit mounted on said first track means for movement along one said path, a coil unit for circulating cooling fluid mounted on said second track means for movement along the other said path, said blower unit comprising a second frame, a blower, and elevator means between said second frame and blower, whereby said blower may be elevated with respect to said second frame.

7. The combination as specified in claim 6, the elevator means mounting said coil unit on said first frame being selectively operable to cause said second path to coincide with said first path whereby after said blower has been elevated in said compartment, said coil unit may be moved into said compartment along a path coincident with the path of movement of said blower unit into said compartment.

8. In a pre-cooler for a refrigerator car having a space between the top of the loading opening ,thereof-and-the ceiling, a blower unit, adapted to circulate the air Within said can a cooling coil unit adapted to cool said air as circulated .by said blower unit, a common mobile frame on which said units are mounted externally of said car. first means carried by said frame and adapted to mount one of said units for projection intosaid car along a path below the top of said opening, and elevate the same into said space, and second means carried by said frame and adapted to mount the other of said units for elevation into said path and for translation along said path into said car in juxtaposed cooperative positionbeneath said first unit contiguous to the ceiling of the car.

9. In a pre-cooling unit for a shipping compartment, means including rails adapted to be positioned within said compartment to provide guide tracks, a blower section adapted to be guidably supportedonsaid tracks for movement into and out of said compartment, said section including a pair of parallel beams, a power-driven'blower, and jack means supporting said blower on said beams and operable to elevate the same from a first position substantially between said beams to a second position above said beams, a cooling coil section, a pair of parallel guides carried'by said beams respectively, elevator means for'supporting said cooling coil section externally of said compartment and operable "to elevate the same to the level of said guides whereby said cooling coil section may be moved into said compartment in cooperative juxtaposed relation with and below said blower when said blower has been elevated to said second position.

10. A pre-cooling apparatus comprising a frame, first and second track means defining substantially horizontal parallel superposed paths, first and second elevating means each mounting a respective track means on said frame for vertical adjustment thereon, a blower unit mounted on said first track means for translation along the path defined thereby, a cooling coil unit mounted on said second track means for translation along the path defined thereby, whereby said units may be individually projected along said frame into a superposed cooperative relation within a compartment to be cooled.

11. In a cooling apparatus, a frame adapted to be positioned adjacent the door opening of a compartment to be cooled, first and second superposed track means defining parallel paths,.means mounting said track means for independent vertical adjustment on said frame, a blower unit mounted for guided translation on and along said first track means, and a cooling coil unit mounted for guided translation on and along said second track means, whereby said units may be projectedindependently in cooperative superposed relation into said compartment.

12. In a pro-cooling apparatus for railway refrigerator cars, a carrier, a support including substantially horizontal first track means, means mounting said support on said carrier and operable to vertically move said support relatively to said carrier, a blower unit mounted for translation onand along said first track means, second track means, means mounting said second track means on said support, and operable to vertically move said second track means relatively to said support and first track means, and a cooling coil unit mounted for translation on and along said second track means in juxtaposed cooperative relation with said blower unit.

13. In a pro-cooling unit for railway refrigerator cars, a carrier truck, a support including a 17 first pair of tracks, means mounting said support on said truck and operable to vertically move said support, relatively to said truck, a second pair of tracks, means mounting said second tracks on said support and operable to vertically move the same relatively to said support, all said tracks being substantially parallel, a blower unit mounted on said first pair of tracks, a cooling coil unit mounted on said second pair of tracks beneath said blower unit, said blower unit including an open-ended frame, a power-driven blower, and means mounting said blower on said frame and operable to vertically move the same between a first position within said frame and a second position above said frame, and a third pair of tracks carried by said frame to translatably support said cooling coil unit when said blower unit is positioned within a car with said blower elevated into said second position.

14. The combination specified in claim 13, and an auxiliary'track support adapted to be mounted in said car above the lading therein, said first pair of tracks being vertically movable into alignment with the tracks of said auxiliary support, whereby to form therewith continuous tracks into said car for said blower unit.

15. In pro-cooling apparatus for a railway refrigerator car, a first track means adapted to be positioned Within said car to extend from one opening thereof, a carrier, a second track means, first elevator means mounting said second track means on said carrier whereby said second track means may be elevated into agreement with said first track means to form therewith a continuous track when said carrier is positioned outside said car adjacent said door opening, a fan unit mounted for translation on and along said first and second track means, said fan unit comprising a pair of connected beams, power-driven fan means, and second elevator means carried by said beams and operable to raise said fan means from a first position between said beams, to a second position above said beams, to thereby provide a space between said beams, a third track means on said means, fourth track means, third elevator means mounting said fourth track means on said carrier for elevation into agreement with said third track means, to form therewith a, continuous track into said car, a cooling coil unit mounted on said fourth track means, whereby said cooling coil unit may be moved into said car on and along said third track means into the space vacated by said fan means when the latter has been elevated to said second position.

16. The combination as specified in claim 15, said fan means including shrouds adapted to direct air drawn over and through said cooling coil unit toward each end of said car above the lading therein.

17. In a pre-cooler for shipping compartments, a frame, having first and second parallel track means mounted thereon, a blower unit supported on said first track means for translation therealong, a cooling coil unit supported on said second track means for translation therealong, said units being in initial superposed cooperative relation for individual movement along the respective track means.

18. In a pre-cooler for refrigerator cars, a frame having a first and second pairs of superposed parallel tracks thereon a blower unit and a cooling coil unit mounted on said respective pairs of tracks for guided translation therealong,

said cooling unit comprising a pair of spaced parallel beams, a third pair of tracks, each track of said third pair being on the inner wall of a respective beam, a power-driven blower and elevator means operable to raise said blower from a first position substantially between said beams, to a second position above the same whereby said cooling coil unit may be moved on and along said third pair of tracks into cooperative relation with and beneath said blower.

19. The pre-cooler as specified in claim 18, said elevator means comprising, a pair of shafts, each journaled on a respective beam, a pair of winding spools on each shaft, a plurality of cable means each adapted to be wound on a respective spool and having its lower end attached to said blower, and means connecting said shafts for simultaneous rotation to thereby elevate said blower into said second position.

20. In a pre-cooling apparatus for a railway refrigerator car, frame means forming a first pair of horizontal track members extending over the lading in said car between loading doors and extending through one door exteriorly of said car, a fan unit mounted on said track members for translation therealong into and out of said car, said unit comprising a pair of laterally spaced beams rigidly united at their ends, a power-driven fan, and elevator means operable to move said fan from a position between said beams to a position above said beams to thereby provide a space between said beams, a second pair of horizontal track members carried by said beams, a third pair of track members, elevator means mounting said third pair of track members on said frame means for elevation into alignment with the respective tracks of said second pair of track members, and a cooling coil unit mounted for translation on and along said second and third pairs of track members into said car into the space vacated by said fan.

21. The combination as specified in claim 20, said coil unit having connections for circulating therethrough a fluid heat exchange medium from a source externally of said car.

22. In a heat exchange device, a supporting frame comprising rigidly interconnected laterally spaced parallel beams, a blower assembly, elevator means mounting said assembly on and between said beams and operable to move said assembly from a first position between said beams to a second position substantially elevated above said beams, a heat exchange unit, and track means carried by said beams for supporting said heat exchange unit for translation along and between said beams when said blower assembly is I in said second position.

28. A heat exchange device as in claim 22, said track means comprising horizontal tracks carried by said beams respectively, said heat-exchange unit having rollers movable on and along said tracks, whereby said unit may be moved through an open end of said frame between said beams, into the space vacated by said blower assembly when the latter is moved to second position.

24. In a pro-cooler for a railway refrigerator car, a blower unit comprising a rigid frame including a pair of normally horizontal laterally spaced beams, a blower, means carried by said beams and mounting said blower for vertical movement therebetween from a first position between said beams to a second position above said beams, normally horizontal track means carried by said beams, and a coo-ling coil unit mounted for translation on and along said track means he l9 2% tween said beams when said blower is in second REFERENCES CITED posmon- The following references are of'recordin the 25. In a refrigerator device, a frame comprising fil of hi I te closed side walls, said frame having one end, top 6 t S andbottom open, a pair of parallel tracks, one 5 UNITED STATES PATENTS said track being carried by the inside surface of a respective one of said side Walls, and a heat exg gg g H g D change unit adapted to be supported on and by 2323439 gg 3? 1943 said tracks for translation between said side Walls. 2,477,250 Hmcz July 26, 1949 10 BROADUS WILSON. 

